Digital forensics and computer security auditing are two areas that require accurate snapshots of a computer's state. Accurate knowledge of the state of a computer, including memory contents, can be vital in tracking nefarious code, determining criminal activity, ensuring compliance to corporate policies, etc.
However, as in many other disciplines, the act of measuring can often influence the measurement. Programs running on a computer that are used measure the computer by definition change the state of the computer. It may be difficult or impossible to get an accurate snapshot of memory state, paging, execution state, etc. when a program must be loaded and active to take the measurement.
In addition, especially when trying to detect unauthorized code, such as a virus, a concern is that the measurement program itself may be compromised and any results returned may not be accurate.
Once the measurement has been made, the results must still be delivered for evaluation. While being stored or in transit, results data may be subject to attack. When the results data are large, e.g. a gigabyte or more, the problem of transport may be increased.